Test device and method

ABSTRACT

A test device and a method are provided in the invention. The test device includes a first connection interface, a storage device, a processor and a second connection interface. The first connection interface is coupled to a device under test (DUT) and obtains power information from the DUT according to a first instruction. The storage device stores the power information. The processor is coupled to the first connection interface and storage device, when the first connection interface is coupled to the DUT, sends the first instruction to the first connection interface, receives the power information from the first connection interface, and stores the power information in the storage device. The second connection interface is coupled to an external controlling system, sends the power information to the external controlling system and receives a test instruction from the external controlling system to test the DUT.

CROSS REFERENCE TO RELATED APPLICATIONS

This Application claims priority of Taiwan Patent Application No.105119517, filed on Jun. 22, 2016, the entirety of which is incorporatedby reference herein.

BACKGROUND OF THE INVENTION Field of the Invention

The invention generally relates to testing technology for UniversalSerial Bus (USB) Type-C Power-Delivery (PD), and more particularly, totesting technology for automatically testing USB Type-C PD throughserial communication by a test device.

Description of the Related Art

As technology advances, the standard of USB is continuously beingmodified and upgraded. USB 3.0 Promoter Group declared that thedevelopment of the USB Type-C connector started in December, 2013, andthe new standard was specified in 2014. The Type-C connector wasdeveloped based on the technologies of USB 3.0 and USB 2.0. Therefore,for transmission performance, the Type-C connector can support USB 3.1high-speed transmission (10 Gbit/s) and the size of the Type-C connectoris compatible with the connector size specified in the standards of USB3.0 and USB 2.0. In addition, because both the upper side and the lowerside of the USB Type-C connector are configured pins, the Type-Cconnector (interface) can support reversible plug orientation. Namely,the user can use the Type-C connector without regard to plugorientation.

Further, the USB type-C connector can be utilized with the USB-PDtechnology. USB-PD technology is a power transmission (charge/discharge)standard specified by the USB Implementers Forum (USB-IF). It is definedin the USB-PD standard that the structure of USB-PD comprises a Sourceand a Sink. Different profiles are specified in the USB-PD standard toprovide different voltages and currents to meet the requirements ofdifferent electronic devices.

FIG. 1 is a block diagram of a test system 10 according to the prior artof the invention. As shown in FIG. 1, when a device under test (DUT) 11is tested, the DUT 11 may be connected to a control board 12, a powersource 13, and a load 14. However, in current test of the USB Type-C PDdevice (i.e. DUT 11), the user needs to operate the control board 12manually to switch different test settings (i.e. different groups ofvoltages and currents that the DUT 11 can provide to the load 14) totest the different groups of voltages and currents which the USB Type-CPD device supports. Therefore, how to test the USB Type-C PD deviceautomatically and efficiently is an important subject.

BRIEF SUMMARY OF THE INVENTION

A test device and method for automatically testing USB Type-C PD throughserial communication are provided to overcome the problems mentionedabove.

An embodiment of the invention provides a test device. The test devicecomprises a first connection interface, a storage device, a processorand a second connection interface. The first connection interface iscoupled to a device under test (DUT) and obtains power information fromthe DUT according to a first instruction. The storage device stores thepower information. The processor is coupled to the first connectioninterface and storage device, and when the first connection interface iscoupled to the DUT, it sends the first instruction to the firstconnection interface. In addition, the processor receives the powerinformation from the first connection interface and stores the powerinformation in the storage device. The second connection interface,which is coupled to an external controlling system, sends the powerinformation to the external controlling system and receives a testinstruction from the external controlling system to test the DUT.

In some embodiments of the invention, the test device further comprisesa first controller and a second controller. The first controller iscoupled to the first connection interface and the processor, andconverts a first communication format which is applicable to the firstconnection interface to a second communication format which isapplicable to the processor. The second controller is coupled to thesecond connection interface and the processor, and converts the secondcommunication format which is applicable to the processor to a thirdcommunication format which is applicable to the second connectioninterface. In some embodiments of the invention, the test device onlycomprises a first controller, and the processor converts the secondcommunication format which is applicable to the processor to a thirdcommunication format which is applicable to the second connectioninterface.

In some embodiments of the invention, the processor sends a powerrequest to the DUT through the first connection interface according tothe test instruction to inform the DUT that the DUT needs to providepower corresponding to the power request. In some embodiments of theinvention, when the external controlling system sends a serialinstruction to request the power information of the DUT, the test devicesends the power information to the external controlling system throughthe second connection interface and the external controlling systemsends the test instruction to the second connection interface accordingto the power information. In some embodiments of the invention, thestorage device stores a look-up table and the power information storedin the look-up table.

An embodiment of the invention provides a test device. The test devicecomprises a first connection interface, a processor and a secondconnection interface. The first connection interface is coupled to adevice under test (DUT) and obtains power information from the DUTaccording to a first instruction. The processor is coupled to the firstconnection interface and comprises a storage device. The processor sendsthe first instruction to the first connection interface when the firstconnection interface is coupled to the DUT, receives the powerinformation from the first connection interface, and stores the powerinformation in the storage device. The second connection interface iscoupled to an external controlling system sends the power information tothe external controlling system and receives a test instruction from theexternal controlling system to test the DUT.

An embodiment of the invention provides test method which is applied ina test device. The test method comprises the steps of sending a firstinstruction to the DUT through the first connection interface to obtainpower information from the DUT when a first connection interface of thetest device is coupled to a device under test (DUT); storing the powerinformation in a storage device, wherein the storage device isexternally connected to a processor of the test device; sending thepower information to the external controlling system through a secondconnection interface of the test device when an external controllingsystem sends a serial instruction to request the power information ofthe DUT; receiving a test instruction from the external controllingsystem through the second connection interface to test the DUT.

An embodiment of the invention provides a test method which is appliedin a test device. The test method comprises the steps of sending a firstinstruction to the DUT through the first connection interface to obtainpower information from the DUT when a first connection interface of thetest device is coupled to a device under test (DUT); storing the powerinformation in a storage device, wherein the storage device is comprisedin a processor of the test device; sending the power information to theexternal controlling system through a second connection interface of thetest device when an external controlling system sends a serialinstruction to request the power information of the DUT; and receiving atest instruction from the external controlling system through the secondconnection interface to test the DUT.

Other aspects and features of the invention will become apparent tothose with ordinary skill in the art upon review of the followingdescriptions of specific embodiments of test devices and methods.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will become more fully understood by referring to thefollowing detailed description with reference to the accompanyingdrawings, wherein:

FIG. 1 is a block diagram of a test system 10 according to the prior artof the invention;

FIG. 2A is a block diagram of a test device 100 according to anembodiment of the invention;

FIG. 2B is a block diagram of a test device 100 according to anotherembodiment of the invention;

FIG. 2C is a block diagram of a test device 100 according to anotherembodiment of the invention;

FIG. 2D is a block diagram of a test device 100 according to anotherembodiment of the invention;

FIG. 3 is a flow chart 300 illustrating the test method according to anembodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The following description is of the best-contemplated mode of carryingout the invention. This description is made for the purpose ofillustrating the general principles of the invention and should not betaken in a limiting sense. The scope of the invention is best determinedby reference to the appended claims.

FIG. 2A is a block diagram of a test device 100 according to anembodiment of the invention. As shown in FIG. 2A, the test device 100comprises a first connection interface 110, a first controller 120, aprocessor 130, a second controller 140, a second connection interface150 and a storage device 160. Note that, in order to clarify the conceptof the invention, FIG. 2A presents a simplified block diagram in whichonly the elements relevant to the invention are shown. However, theinvention should not be limited to what is shown in FIG. 2A. The testdevice 100 can also comprise other elements.

In an embodiment of the invention, the test device 100 may be a controlboard. In embodiment of the invention, a device under test (DUT) 200 maybe an electronic device which supports the USB type-C Power Delivery(PD) function. When the DUT 200 is tested, the test device 100 can beregarded as a Sink and the DUT 200 can be regarded as a Source.

In an embodiment of the invention, the first connection interface 110may be a USB type-C connection interface, and is coupled to a firstcontroller 120. When the DUT 200 is tested, the first connectioninterface 110 will be coupled to the DUT 200. The test device 100 cancommunicate with the DUT 200 (e.g. send instructions to DUT 200) andobtain the power information of the DUT 200 from the DUT 200 through aConfiguration Channel pin (CC pin) of the USB type-C connectioninterface (i.e. the first connection interface 110). In an embodiment ofthe invention, the DUT 200 further comprises a connection interfacecorresponding to the first connection interface 110. The DUT 200 can becoupled to the first connection interface 110 of the test device 100through the connection interface for the test.

In an embodiment of the invention, the second connection interface 150is a serial communication interface, such as a RS-232 interface, aRS-485interface, and an I2C interface, but the invention should not belimited to these interfaces. The second connection interface 150 iscoupled to the second controller 140 and an external controlling system300. In an embodiment of the invention, the external controlling system300 may be a computer device and comprise a connection interfacecorresponding to the second connection interface 150. The externalcontrolling system 300 can be coupled to the second connection interface150 of the test device 100 through this connection interface. In theembodiments of the invention, the external controlling system 300 maysend instructions to the second connection interface 150 to proceed withthe test of the DUT 200.

In an embodiment of the invention, the first controller 120 is coupledto the first connection interface 110 and processor 130. The firstcontroller 120 is configured to convert the data or signals communicatedbetween the first connection interface 110 and the processor 130 to theapplicable communication format for the first connection interface 110and the processor 130. That is to say, the first controller 120 mayconvert a first communication format which is applicable to the firstconnection interface 110 to a second communication format which isapplicable to the processor 130, and convert the second communicationformat which is applicable to the processor 130 to the firstcommunication format which is applicable to the first connectioninterface 110.

In an embodiment of the invention, the second controller 140 is coupledto the second connection interface 150 and the processor 130. The secondcontroller 140 is configured to convert the data or signals communicatedbetween the second connection interface 150 and the processor 130 to theapplicable communication format for the second connection interface 150and the processor 130. That is to say, the second controller 140 mayconvert the second communication format which is applicable to theprocessor 130 to a third communication format which is applicable to thesecond connection interface 150, and convert the third communicationformat which is applicable to the second connection interface 150 to thesecond communication format which is applicable to the processor 130.

In another embodiment of the invention, as shown in FIGS. 2B and 2D, thetest device 100 may not comprise the second controller 140. That is tosay, in this embodiment, the processor 130 can comprise the function ofthe second controller 140. Therefore, the processor 130 may directlyconvert the data or signals communicated between the second connectioninterface 150 and the processor 130 to the applicable communicationformat for the second connection interface 150 and the processor 130.That is to say, the processor 130 may convert the second communicationformat which is applicable to the processor 130 to the thirdcommunication format which is applicable to the second connectioninterface 150, and convert the third communication format which isapplicable to the second connection interface 150 to the secondcommunication format which is applicable to the processor 130.

In an embodiment of the invention, the storage device 160 is coupled tothe processor 130. In the embodiments of the invention, the storagedevice 160 may be configured to store the power information of the DUT200 in a look-up table (LUT). The storage device 160 may be a volatilememory (e.g. Random Access Memory (RAM)), or a non-volatile memory (e.g.a flash memory, Read Only Memory (ROM)), a hard disc or a combination ofthe memory devices listed above. In another embodiment of the invention,as shown in FIGS. 2C and 2D, the storage device 160 may be integrated inthe processor 130.

In an embodiment of the invention, the processor 130 may be amicrocontroller unit (MCU). In an embodiment of the invention, theprocessor 130, the first controller 120 and the second controller 140may be integrated in a chip.

In an embodiment of the invention, when the DUT 200 is tested, the firstconnection interface 110 will be coupled to the DUT 200. When the firstconnection interface 110 is coupled to the DUT 200, the processor 130may send a first instruction S1 to the DUT 200 through the firstconnection interface 110 to obtain power information S2 from the DUT200. In an embodiment of the invention, the power information S2 maycomprise a plurality of groups (e.g. 6 groups, but the invention shouldnot be limited to this) of voltage values and current values which theDUT 200 can provide. After the processor 130 obtains the powerinformation S2 of the DUT 200, the processor 130 may store the powerinformation S2 of the DUT 200 in the look-up table of the storage device160.

In an embodiment of the invention, when the second connection interface150 is coupled to the external controlling system 300, and the externalcontrolling system 150 sends a first serial instruction S3 to the testdevice 100 to ask the test device 100 to provide the power informationS2 of DUT 200, according to the first serial instruction S3 receivedfrom the second connection interface 150, the processor 130 may providethe power information S2 of the DUT 200 stored in the look-up table ofthe storage device 160 to the external controlling system 300 throughthe second connection interface 150.

After the external controlling system 300 obtains the power informationS2 of the DUT 200, the external controlling system 300 can know whichgroups of voltage and current values the DUT 200 can provide. Then, theexternal controlling system 300 may send a test instruction S4 to thesecond connection interface 150 to inform the test device 100 whichgroup of voltage and current values of the DUT 200 will have its powerdelivery tested. When the processor 130 receives the test instruction S4from the external controlling system 300, the processor 130 may send apower request S5 (Request signal) to the DUT 200 through the firstconnection interface 110 according to the test instruction S4 to informthe DUT 200 that the DUT 200 needs to provide power (i.e. the group ofvoltage and current values which the external controlling system 300wants to test) corresponding to the power request S5. For example, whenthe external controlling system 300 knows that the DUT 200 can provide 6groups of voltage and current values according to the power informationS2, if the external controlling system 300 desires to test the powerdelivery for the second group of voltage and current values of the DUT200, the external controlling system 300 may send the test instructionS4 to the second connection interface 150 to inform the test device 100that the power delivery for the second group of voltage and currentvalues of the DUT 200 will be tested. When the processor 130 receivesthe test instruction S4 from the external controlling system 300, theprocessor 130 may send a power request S5 to the DUT 200 through thefirst connection interface 110 according to the test instruction S4 toinform the DUT 200 that the DUT 200 needs to provide the second group ofvoltage and current values.

When the DUT 200 receives the power request S5, if the DUT can providethe power (i.e. the group of voltage and current values which theexternal controlling system 300 wants to test) corresponding to thepower request S5, the DUT 200 may send an Accept signal to the testdevice 100 to inform the test device 100 that it can provide the powercorresponding to the power request S5. When the DUT 200 has prepared thepower corresponding to the power request S5 (i.e. the DUT 200 hasswitched to the group of voltage and current values which needs to betested), the DUT 200 may send a PS_RDY signal to the test device 100 toinform the test device 100 that it has prepared the power correspondingto the power request S5.

When the test device 100 receives the Accept signal and the PS_RDYsignal, the test device 100 may record the Accept signal and the PS_RDYsignal in the look-up table. When the external controlling device 300sends a second serial instruction S6 to inquire of the test device 100about the preparation state of the group of voltage and current values(i.e. the group of voltage and current values which the externalcontrolling system 300 wants to test), the test device 100 may informthe external controlling system 300 that the DUT 200 has prepared thegroup of voltage and current values which the external controllingsystem 300 wants to test, and inform the DUT 200 that the DUT 200 needsto provide the group of voltage and current values which the externalcontrolling system 300 wants to test to the external controlling system300 to test the power delivery for this group of voltage and currentvalues of the DUT 200.

FIG. 3 is a flow chart 3000 illustrating the test method according to anembodiment of the invention. The test method is applied to the testdevice 100. As shown in FIG. 3, in step S3010, when a first connectioninterface of the test device is coupled to a DUT, the test device sendsa first instruction to the DUT through the first connection interface toobtain power information from the DUT. In step S3020, the powerinformation is stored in a storage device after the test device obtainedthe power information. In step S3030, when a second connection interfaceof the test device is coupled an external controlling system, and theexternal controlling system sends a serial instruction to request thepower information of the DUT, the test device sends power information tothe external controlling system through the second connection interface.In step S3040, the test device receives a test instruction from theexternal controlling system through the second connection interface totest the DUT. In an embodiment of the invention, the power informationmay be stored in a look-up table of the storage device.

In an embodiment of the invention, the storage device is connected to aprocessor of the test device externally. In another embodiment of theinvention, the storage device is comprised in a processor of the testdevice.

In an embodiment, the test method further comprises the steps of that afirst controller converts a first communication format which isapplicable to the first connection interface to a second communicationformat which is applicable to the processor of the test device; and asecond controller converts the second communication format which isapplicable to the processor to a third communication format which isapplicable to the second connection interface. In another embodiment,the test method further comprises the steps of that a first controllerconverts a first communication format which is applicable to the firstconnection interface to a second communication format which isapplicable to the processor of the test device; and the processorconverts the second communication format which is applicable to theprocessor to a third communication format which is applicable to thesecond connection interface.

In an embodiment of the invention, the test method further comprises thestep of sending test instruction to the second connection interfaceaccording to the power information by the external controlling system.In an embodiment of the invention, the test method further comprises thestep of sending a power request to the DUT through the first connectioninterface according to the test instruction by the test device to informthe DUT that the DUT needs to provide power corresponding to the powerrequest.

According to the test method provided by the embodiments of theinvention, different groups of voltage and current values which aresupported by the test device can be tested by a test device throughserial communication to achieve the automatic testing of the USB Type-CPD.

The steps of the method described in connection with the aspectsdisclosed herein may be embodied directly in hardware, in a softwaremodule executed by a processor, or in a combination of the two. Asoftware module (e.g., including executable instructions and relateddata) and other data may reside in a data memory such as RAM memory,flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a harddisk, a removable disk, a CD-ROM, or any other form of computer-readablestorage medium known in the art. A sample storage medium may be coupledto a machine such as, for example, a computer/processor (which may bereferred to herein, for convenience, as a “processor”) such that theprocessor can read information (e.g., code) from and write informationto the storage medium. A sample storage medium may be integral to theprocessor. The processor and the storage medium may reside in an ASIC.The ASIC may reside in user equipment. In the alternative, the processorand the storage medium may reside as discrete components in userequipment. Moreover, in some aspects, any suitable computer-programproduct may comprise a computer-readable medium comprising codesrelating to one or more of the aspects of the disclosure. In someaspects, a computer software product may comprise packaging materials.

It should be noted that although not explicitly specified, one or moresteps of the methods described herein can include a step for storing,displaying and/or outputting as required for a particular application.In other words, any data, records, fields, and/or intermediate resultsdiscussed in the methods can be stored, displayed, and/or output toanother device as required for a particular application. While theforegoing is directed to embodiments of the present invention, other andfurther embodiments of the invention can be devised without departingfrom the basic scope thereof. Various embodiments presented herein, orportions thereof, can be combined to create further embodiments. Theabove description is of the best-contemplated mode of carrying out theinvention. This description is made for the purpose of illustrating thegeneral principles of the invention and should not be taken in alimiting sense. The scope of the invention is best determined byreference to the appended claims.

The above paragraphs describe many aspects. Obviously, the teaching ofthe invention can be accomplished by many methods, and any specificconfigurations or functions in the disclosed embodiments only present arepresentative condition. Those who are skilled in this technology willunderstand that all of the disclosed aspects in the invention can beapplied independently or be incorporated.

While the invention has been described by way of example and in terms ofpreferred embodiment, it is to be understood that the invention is notlimited thereto. Those who are skilled in this technology can still makevarious alterations and modifications without departing from the scopeand spirit of this invention. Therefore, the scope of the presentinvention shall be defined and protected by the following claims andtheir equivalents.

What is claimed is:
 1. A test device, comprising: a first connectioninterface, coupled to a device under test (DUT) and obtaining powerinformation from the DUT according to a first instruction; a storagedevice, storing the power information; a processor, coupled to the firstconnection interface and storage device, when the first connectioninterface is coupled to the DUT, sending the first instruction to thefirst connection interface, receiving the power information from thefirst connection interface, and storing the power information in thestorage device; and a second connection interface, coupled to anexternal controlling system, sending the power information to theexternal controlling system and receiving a test instruction from theexternal controlling system to test the DUT.
 2. The test device of claim1, further comprising: a first controller, coupled to the firstconnection interface and the processor, and converting a firstcommunication format which is applicable to the first connectioninterface to a second communication format which is applicable to theprocessor; and a second controller, coupled to the second connectioninterface and the processor, and converting the second communicationformat which is applicable to the processor to a third communicationformat which is applicable to the second connection interface.
 3. Thetest device of claim 1, further comprising: a first controller, coupledto the first connection interface and the processor, and converting afirst communication format which is applicable to the first connectioninterface to a second communication format which is applicable to theprocessor.
 4. The test device of claim 3, wherein the processor convertsthe second communication format which is applicable to the processor toa third communication format which is applicable to the secondconnection interface.
 5. The test device of claim 1, wherein the firstconnection interface is a USB Type-C connection interface, and thesecond connection interface is a serial communication interface.
 6. Thetest device of claim 5, wherein the first connection interface obtainsthe power information of the DUT through a configuration channel (CC)pin of the USB Type-C connection interface.
 7. The test device of claim1, wherein the processor sends a power request to the DUT through thefirst connection interface according to the test instruction to informthe DUT that the DUT needs to provide power corresponding to the powerrequest.
 8. The test device of claim 7, wherein when the externalcontrolling system sends a serial instruction to request the powerinformation of the DUT, the test device sends the power information tothe external controlling system through the second connection interfaceand the external controlling system sends the test instruction to thesecond connection interface according to the power information.
 9. Thetest device of claim 1, wherein the storage device stores a look-uptable, and the power information stored in the look-up table.
 10. A testdevice, comprising: a first connection interface, coupled to a deviceunder test (DUT) and obtaining power information from the DUT accordingto a first instruction; a processor, coupled to the first connectioninterface and comprising a storage device, when the first connectioninterface is coupled to the DUT, sending the first instruction to thefirst connection interface, receiving the power information from thefirst connection interface, and storing the power information in thestorage device; and a second connection interface, coupled to anexternal controlling system, sending the power information to theexternal controlling system and receiving a test instruction from theexternal controlling system to test the DUT.
 11. The test device ofclaim 10, further comprising: a first controller, coupled to the firstconnection interface and the processor, and converting a firstcommunication format which is applicable to the first connectioninterface to a second communication format which is applicable to theprocessor; and a second controller, coupled to the second connectioninterface and the processor, and converting the second communicationformat which is applicable to the processor to a third communicationformat which is applicable to the second connection interface.
 12. Thetest device of claim 10, further comprising: a first controller, coupledto the first connection interface and the processor, and converting afirst communication format which is applicable to the first connectioninterface to a second communication format which is applicable to theprocessor.
 13. The test device of claim 12, wherein the processorconverts the second communication format which is applicable to theprocessor to a third communication format which is applicable to thesecond connection interface.
 14. The test device of claim 10, whereinthe first connection interface is a USB Type-C connection interface, andthe second connection interface is a serial communication interface. 15.The test device of claim 14, wherein the first connection interfaceobtains the power information of the DUT through a configuration channel(CC) pin of the USB Type-C connection interface.
 16. The test device ofclaim 10, wherein the processor sends a power request to the DUT throughthe first connection interface according to the test instruction toinform the DUT that the DUT needs to provide power corresponding to thepower request.
 17. The test device of claim 16, wherein when theexternal controlling system sends a serial instruction to request thepower information of the DUT, the test device sends the powerinformation to the external controlling system through the secondconnection interface and the external controlling system sends the testinstruction to the second connection interface according to the powerinformation.
 18. The test device of claim 10, wherein the storage devicestores a look-up table, and the power information stored in the look-uptable.
 19. A test method, applied in a test device, comprising: when afirst connection interface of the test device is coupled to a deviceunder test (DUT), sending a first instruction to the DUT through thefirst connection interface to obtain power information from the DUT;storing the power information in a storage device, wherein the storagedevice is externally connected to a processor of the test device; whenan external controlling system sends a serial instruction to request thepower information of the DUT, sending the power information to theexternal controlling system through a second connection interface of thetest device; and receiving a test instruction from the externalcontrolling system through the second connection interface to test theDUT.
 20. The test method of claim 19, further comprising: converting, bya first controller, a first communication format which is applicable tothe first connection interface to a second communication format which isapplicable to the processor; and converting, by a second controller, thesecond communication format which is applicable to the processor to athird communication format which is applicable to the second connectioninterface.
 21. The test method of claim 19, further comprising:converting, by a first controller, a first communication format which isapplicable to the first connection interface to a second communicationformat which is applicable to the processor; and converting, by theprocessor, the second communication format which is applicable to theprocessor to a third communication format which is applicable to thesecond connection interface.
 22. The test method of claim 19, whereinthe first connection interface is a USB Type-C connection interface, andthe second connection interface is a serial communication interface. 23.The test method of claim 22, further comprising: obtaining the powerinformation of the DUT through a configuration channel (CC) pin of theUSB Type-C connection interface.
 24. The test method of claim 19,further comprising: sending a power request to the DUT through the firstconnection interface according to the test instruction to inform the DUTthat the DUT needs to provide power corresponding to the power request.25. The test method of claim 24, further comprising: sending, by theexternal controlling system, the test instruction to the secondconnection interface according to the power information.
 26. The testmethod of claim 19, further comprising: storing the power information ina look-up table of the storage device.
 27. A test method, applied in atest device, comprising: when a first connection interface of the testdevice is coupled to a device under test (DUT), sending a firstinstruction to the DUT through the first connection interface to obtainpower information from the DUT; storing the power information in astorage device, wherein the storage device is comprised in a processorof the test device; when an external controlling system sends a serialinstruction to request the power information of the DUT, sending thepower information to the external controlling system through a secondconnection interface of the test device; and receiving a testinstruction from the external controlling system through the secondconnection interface to test the DUT.
 28. The test method of claim 27,further comprising: converting, by a first controller, a firstcommunication format which is applicable to the first connectioninterface to a second communication format which is applicable to theprocessor; and converting, by a second controller, the secondcommunication format which is applicable to the processor to a thirdcommunication format which is applicable to the second connectioninterface.
 29. The test method of claim 27, further comprising:converting, by a first controller, a first communication format which isapplicable to the first connection interface to a second communicationformat which is applicable to the processor; and converting, by theprocessor, the second communication format which is applicable to theprocessor to a third communication format which is applicable to thesecond connection interface.
 30. The test method of claim 27, whereinthe first connection interface is a USB Type-C connection interface, andthe second connection interface is a serial communication interface. 31.The test method of claim 30, further comprising: obtaining the powerinformation of the DUT through a configuration channel (CC) pin of theUSB Type-C connection interface.
 32. The test method of claim 27,further comprising: sending a power request to the DUT through the firstconnection interface according to the test instruction to inform the DUTthat the DUT needs to provide power corresponding to the power request.33. The test method of claim 32, further comprising: sending, by theexternal controlling system, the test instruction to the secondconnection interface according to the power information.
 34. The testmethod of claim 27, further comprising: storing the power information ina look-up table of the storage device.